Backhaul is the means to transport wireless customer traffic from a radio access cell site to a Mobile Switching Center (MSC) or Worldwide Interoperability for Microwave Access (WiMAX) Service Center. Backhaul technologies include point-to-point microwave radio relay transmission, point-to-multipoint microwave access technologies (such as Local Multipoint Distribution Service (LMDS), WiFi, and WiMAX), digital subscriber line (DSL) variants (such as Asymmetric Digital Subscriber Line (ADSL) and Single-pair High-speed Digital Subscriber Line (SHDSL)), Plesiochronous Digital Hierarchy (PDH) and Synchronous Digital Hierarchy (SDH)/synchronous optical networking (SONET) interfaces (such as (fractional) E1/T1, E3, T3, and Synchronous Transport Module (STM)-1/Optical Carrier (OC)-3), IP (Internet Protocol)/MPLS (Multi-Protocol Label Switching), and Ethernet. Backhaul can be used as a facility pipe for multiplexing and transport of individual Radio Access Network circuits and connections. Additionally, backhaul capacity may be leased, in full or in part, from a third party service provider.
A packet network has inherent variability in timing and spacing between packets. Currently, measuring one way frame delay is accomplished by measuring the round trip delay and dividing by two. However, round trip delay does not take into account the asymmetrical paths that Ethernet uses. Also, the latency or delay from the MSC to the BTS (Base Transceiver Station) may be different than the latency in the opposite direction. Thus, it is possible that round trip delay divided by two will not yield an accurate one way frame delay measurement.